What is Lassa fever and why is it dangerous?

Recently in the UK were recordedcases of Lassa fever. This was rather unexpected news, because this disease is usually found only in West Africa. The investigation showed that the sick people were members of the same family who had just returned from Africa. One of the patients successfully recovered, but the other died, despite the prescribed treatment. There is no vaccine for Lassa fever, but the disease is considered very dangerous for the human body. At the moment, the UK authorities are investigating other likely cases of the disease. A number of questions arise: is there a risk of Lassa fever spreading around the world, how does it destroy the body and through what is it transmitted? Scientists already have the answers.

Lassa fever is caused by rodents.


  • 1 Discovery of Lassa fever
  • 2 How do you get Lassa fever?
  • 3 Symptoms of Lassa Fever
  • 4 Lassa fever treatment
  • 5 Risk of spreading Lassa fever

Discovery of Lassa fever

The disease was first described in the 1950s, butthe pathogen was found only in 1969, during the study of an infected person from the Nigerian city of Lassa. The virus is called Lassa mammarenavirus and replicates inside rodents. The virus has a spherical shape and has a shell, on the surface of which there are villi with a diameter of up to 150 nanometers. As a rule, reservoirs for the development of the virus are polynipple rats of the Mastomys species. They themselves do not suffer from the disease, but spread the virus through urine and droppings. The virus also thrives and multiplies in the kidneys of the green monkey (Chlorocebus sabaeus).

The causative agent of Lassa disease under a microscope

How do you get Lassa fever?

Villagers are at risk becausetraces of urine and droppings of infected animals are usually found there. Today, the disease is common in Benin, Guinea, Ghana, Liberia and other West African countries. Every year, up to 500,000 cases of the disease are registered in these countries, and about 5,000 of those infected die. The cause of death is usually untimely assistance - with proper treatment, people stay alive.

Rat species Mastomys

The virus is transmitted from animals to humans through theirwaste products. Sometimes a person imperceptibly touches the place where the rodents crap and does not wash their hands after that. While eating, the virus enters the food, and then ends up inside the human body. From person to person, the Lassa virus is also transmitted through feces and urine, and cases of infection through sexual contact have also been recorded. Cases of spread by airborne droplets have not been registered.

See also: How to wash your hands so that they are free of dangerous bacteria?

Lassa fever symptoms

After infection, the disease manifests its symptomsin the period from 6 to 21 days. At first, a person feels weak and his body temperature rises - this is a sign that the virus has begun to act and the body has noticed this and is trying to cope with it. A few days later there is a headache, muscle aches, diarrhea and cough. With the development of complications, the patient's face swells, fluid accumulates in the pulmonary sinuses, blood flows from the mouth, nose, and so on. At an extreme degree of the disease, a person falls into a state of shock and even to a coma.

Lassa fever is common in West Africa

Lassa fever treatment

Generally speaking, Lassa fever strikesrespiratory organs, central nervous system and kidneys. Since the disease has symptoms similar to other types of fevers, it is difficult to diagnose it. Without the use of special tests, it is easy to confuse it with Ebola, malaria, typhoid fever, yellow fever, and so on. Data on the lethality of Lassa fever vary: according to WHO, the risk of death is only 1%, while other sources say much higher rates.

Lassa fever is easily confused with other diseases.

The chances of survival are greatly increased byearly diagnosis. There is no vaccine against Lassa fever because doctors simply prescribe drugs against viruses to patients. Approximately 25% of those who are cured develop deafness, but in half of these people hearing is restored after 1-3 months.

See also: Scientists have found in animals a gene mutation that blocks the reproduction of HIV and the Ebola virus

The risk of spreading Lassa fever

The fact that Lassa fever was found inGreat Britain, alarmed many people. However, given the way it spreads, it cannot cause a new epidemic. Infected people are placed in isolation, and doctors in contact with them are well protected. Given the very slow spread of the Lassa virus, WHO representatives do not consider it a cause for serious concern.

The risk of Lassa fever spreading worldwide is very low

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But this case is another reminderon the importance of hand washing. Residents of rural areas should be most careful, because rodents can carry many other diseases. For example, in Russia, you can pick up "mouse fever", the causative agents of which are several types of viruses at once.